1. Field of the Invention
The present invention relates generally to a multi-layer Flexible Printed Circuit Board (FPCB) for an electronic device, and more particularly to a multi-layer FPCB for an electronic device, in which a plurality of components are provided alternately on a top surface and a bottom surface of a base layer and the components are removed from the other region.
2. Description of the Related Art
Generally, in an electronic device, a multi-layer Flexible Printed Circuit Board (FPCB) is used to electrically connect sections of a portion having one or more curves. The multi-layer FPCB was developed to create a compact and lightweight component for electronic devices. The multi-layer FPCB allows for durable and high-density wiring due to its highly repetitive flexural strength, making it very reliable. The multi-layer FPCB has high thermal resistance, durability, and chemical resistance, and because of its high resistance against heat, the multi-layer FPCB has been widely used as a core component in many electronic devices such as cameras, computers, peripheral devices, portable communication devices, and video and audio devices.
Multi-layer FPCBs may be classified into mono-layer FPCBs and multi-layer FPCBs. The mono-layer FPCB has been the most common, but recently, the multi-layer FPCB has come into wide use in spite of the increase in the thickness of the FPCB due to the increase in the number of components of an electronic device.
As shown in FIGS. 1 and 2, a multi-layer FPCB 10 includes a base layer 11, upper and lower circuit patterns 12 provided on a top surface and a bottom surface of the base layer 11, upper and lower adhesive layers 13 covered onto the upper and lower circuit patterns 12, and insulating/protecting layers 15 provided on a top surface of the upper adhesive layer 13 and a bottom surface of the lower adhesive layer 13.
The multi-layer FPCB includes a circuit-side connector 16 electrically connected with a connector (not shown) of a plurality of FPCBs provided in the electronic device, and the circuit-side connector 16 is connected to the connector (not shown), such that transmission and reception of various signals is achieved.
However, the conventional multi-layer FPCB has low flexibility due to its increase in thickness, which degrades the engagement strength between the connector of the plurality of FPCBs provided in the electronic device and the circuit-side connector. In addition, when the conventional multi-layer FPCB is continuously used for a long period of time, damage and cracking may occur in the circuit-side connector, causing contact failure and thus degrading the reliability of a product.
Therefore, to improve the flexibility of the multi-layer FPCB, there is a need for a device in which circuit patterns, adhesive layers, and insulating/protecting layers are provided alternately on a top surface and a bottom surface of a base layer and the circuit patterns, the adhesive layers, and the insulating/protecting layers are removed from an other-side region than the base layer.